A C/I advantageous satellite system configuration for land mobile applications

Abstract

A satellite system based on the frequency scanning concept has been recently assessed for L‐band land mobile communications. The study – promototed by ESA/ESTEC for an European application mission – has reached an advanced electrical design phase. The selected configuration is particularly advantageous in terms of Carrier‐to‐Intermodulation ratio (C/I) performance, which constitutes a requirement of key‐importance in the envisaged user applications. The advantage in C/I is due to the proper choice of the on‐board transmitter configuration, which adopts power module pairs where the overall power demand is evenly distributed. The consequent improved C/I is then achievable at both transmitter and radiated far field level. The present paper aims a contribution to the design methodology of frequency scanning satellite systems, by joining two key‐aspects: in fact an analytical approach is proposed to demonstrate the C/I advantage achievable through frequency scanning satellite systems and the methodology is applied to a concrete example, the ESA/ESTEC system, whose feasibility has been fully proved in previous studies. The analysis is performed both at transmitter level and in the far field. The main results achieved are hereinafter presented.